MICRO ROBOT SYSTEM

Technical Field

For use at the systems of lab-on-a-chip and biomedical field, it is related to a system positioning or manipulating of micro-scale living cells and artificial particles.

State of The Art

Nowadays, "analysis and manipulation of single cell" in a liquid environment is a developing field and this topic is directly related to robotics. Without petri dish carrying liquids or systems carrying liquid in small amounts (like microfluidic channel), these biological studies may not be carried out in a laboratory environment.

The biggest problem of micro robots, of which the motion in liquid is provided via magnetic field, is the generation of fnctional force due to contacting the channel/dish surface, in which they are located. The processes of micro manipulation are sensitive processes and requires high precision movement. The contact of micro robot with a surface is a motion limiting factor. For the micro-robots who track the movements of magnets, friction with surface decreases sensitivity drastically. At the systems of prior art, while the force of magnetic field attracts the object to downwards or upwards according to the position of the magnet, it makes the micro-robot contacting with the surface of the plate wherein the micro robot is located and therefore most of the magnetic field to be used as motion generation is used to overcome this fnctional force. Even the movement of the micro robot is provided, due to the contacting of the surface and fnctional force, bounces may occur during the movement and this leads to the problems of the positioning on non-desired locations. Hence, the precise movement of the micro robot may not be provided with the desired accuracy, this makes difficult of the manipulation studies and decreases the success rate. In an article, which is a result of technical researches, in the name of "Polymer-Based Wireless Resonant Magnetic Microrobots" and belongs to Hsi-Wen Tung, Massimo Maffioli, Dominic R. Frutiger, Kartik M. Sivaraman, Salvador Pane and Bradley J. Nelson;

The mass having friction, is attached to another mass via a tool similar to spring and the mass becomes contactless mechanically except the link which is constituted with the spring. Whereas in the invention of "The assembly of Micro robot", the micro robot does not have any mechanical contact with the surface under no circumstances. Aforementioned article is based on the movement of micro robot via, compressing a spring via applying electromagnetic field and then extending it via removing the electromagnetic field. Friction always remains at the environment and a mechanical contact is a matter of. And this case is a factor of preventing sensitivity of the motion. It has been seen that the system is uncontrolled during the extension of the spring.

Whereas in the invention of "Micro robot system", due to applying magnetic force to the system continuously, it may be controlled continuously. In addition to this;

In the article, the objective is to compress the polymer spring together with the attractive force generated by the magnetic effect, then move the objects by the repulsive force by removing the magnetic force from the center.

A matter in question is contacting with the surface. And this effects the sensitivity of the motion.

The magnets which will establish magnetic field, is constituted both under and above the micro robot. Whereas in the invention of "Micro robot system, the magnets are only constituted on underside of the micro robot.

In the article, in the micro robot design, only SU8 is used as a polymer material and this material has more weight than water. The object will sink in liquid and again will not lose its contact with the surface.

SU8 is used in this article as a fastening element providing integrity and as a spring material.

The reason for polymer being used as a spring is that it has a low young's modulus.

Previously gold has been used as a spring material. • But with the use of SU8, a more stable motion on the horizontal plane is obtained. This working principle is totally different from the system of the invention of "Micro robot system".

In an article, which is a result of technical researches, in the name of Wireless Manipulation of Single Cells using Magnetic Microtransporters" and belonging to Mahmut Selman Sakar Edward B. Steager, Anthony Cowley, Vijay Kumar and George J. Pappas;

A polymer mixed with a ferromagnetic material (i.e. magnetized later) is being moved in a fluidic via using magnetic field. In the invention of "The assembly of Micro robot"; although the material is ferromagnetic, it does not require any constraint like magnetization. On the other hand, in the system disclosed in this article, there is no levitation, namely there is a mechanical contact with the surface and this causes to problems based on friction (sensitive positioning) to a great extent. In addition to this,

In the article, a robot is designed, consisting of the mixture of polymer and metal powder, similar to the previous studies.

Also in this article the robot remains contacting with the surface.

A robot is designed having a density similar to that of the liquid's but it is not equal to nor below than that of the liquid's. In the invention of "The assembly of Micro robot", a density which is below than liquid is used and therefore the contact with the surface is eliminated.

In the article the purpose of reducing the density is, reducing the frictional force and providing the movement of the objects with less magnetic force.

In the article to prevent the contact with the surface, it has been used a different method. Movement is provided due to the effect of applied magnetic force with a mechanism providing stick/slip action. An effect in the name of "rocking movement" is disclosed for the movement on the surface with this mechanism.

In an article, which is a result of technical researches, in the name of "High-Speed Magnetic Microrobot Actuation in a Microfluidic Chip by a Fine V-Groove Surface" belonging to Masaya Hagiwara, Tomohiro Kawahara, Toru Iijima, and Fumihito Arai; Instead of eliminating totally the frictional force in between the base surface of the micro robot and the base surface of the plate carrying the liquid, it has been tried to reduce with the vibration systems or the surface design of the micro robot. The designed micro robot is prepared via sculpturing V-grooves on a silicon wafer. The fiction force resulted by the liquid on micro robot has been tried to be reduced by reducing the surface area with V-grooves. Due to the reason that friction force may not be overcome with the V-grooves totally, the effect of the friction force has been tried to be reduced with ultrasonic vibrations. However, because the vibration applied to the whole system for the micro robot also effects micro objects (less than 50 micrometers and below) causing uncontrolled movement, it reduces the positioning sensitivity of the living cells and artificial micro particles.

In conclusion, due to the above-mentioned disadvantages and by the reason of the insufficiency of the solutions regarding the matter, a development has been made essential in the related technical field.

Purpose of the Invention

The invention, aims to overcome the disadvantages which occurs because of friction based upon the present problems.

Another aim of the invention is, obtaining more sensitive movement capability and gaining success at the manipulation processes by reducing friction in between the micro robot and the surface carrying the liquid.

The invention is related to a system positioning or manipulating of cells and micro artificial particles via placing in petri dishes or microfluidic channels for using in the biomedical field and systems of lab-on-a-chip. Regarding system comprises; · A micro robot realizing the positioning or manipulation of artificial particles and living cells in micro-scale,

• A micro-manipulator assembly activating the micro-robot with axial movements, At least one magnet positioned on the micro-manipulator assembly, providing movement and stabilizing of the micro-robot via magnetic effect,

A ferromagnetic coating layer positioned at the sub-section of the micro-robot, providing the micro-robot to stay balanced on the liquid, which is in the liquid experiment assembly, via magnetic field effect applied by the magnet,

A liquid experiment assembly bearing the micro-robot and the ferromagnetic coating layer positioned at the sub-section of it,

A substrate constituting the bottom surface of the fluidic environment.

Figures helping the invention to be perceived

Figure-1, micro-robot and ferromagnetic coating plates used in the micro-robot system regarding the invention are indicated.

Figure-2, usage with the petri dish of the micro-robot system regarding the invention is indicated.

Figure-3, the usage of micro-robot system regarding the invention in the microfluidic chip, is indicated.

The figures do not necessitate absolutely to be scaled and the details which are not required to understand the present invention may be ignored. Besides this, the features which is at least substantially equivalent or the features at least having substantially equivalent functions are indicated with the same number.

Description of the reference numbers of the elements

1. Ferromagnetic coating layer

2. Liquid experimental assembly

3. Micro robot

4. Substrate

5. Magnet

6. Micromanipulation assembly Detailed Description of the Invention

In this detailed description, preferred embodiments of the invention are only disclosed for the better understanding of the subject matter and in a form that does not constitute any limiting effect under no circumstances.

For using in the biomedical field and systems of lab-on-a-chip, it is a system realizing positioning or manipulation of cells and micro artificial particles, comprising;

• a ferromagnetic coating layer (1) positioned at the sub section of the micro robot (3), providing the micro-robot (3) to stay balanced on the liquid, which is in the liquid experimental assembly (2), via magnetic field effect applied by the magnet (5).

The micro robot (3), coated with a ferromagnetic coating layer (1), is placed in the liquid experimental assembly (2) (Please see Fig-2). Ferromagnetic coating layer (1) and the micro robot (3) has been in an integrated form. (Please see Fig-1). Said ferromagnetic coating layer (1) and the micro robot (3) moves together. The micro robot (3) is in a form of polymer having a density which is equal to or below than the liquid's density to be used in the system. Impermeability of the liquids in the liquid experimental assembly (2) is provided and sealed by using the substrate (4) (Please see Fig-3). The micro robot (3) is moved contactless with the effect of magnetic wave propagated by the magnet (5). The forces of the magnetic field which is in the same direction of the gravitational force, constitutes an opposite force to the buoyancy force of the liquid. These three forces are balanced and the micro robot (3) stays suspended in the liquid and micro robot's (3) no interaction remains with the liquid experimental assembly (2) and therefore the frictional force with the surface goes zero. Thus, micro robot (3) is being moved to the desired direction in the liquid, only with using the forces of the magnetic field under parallel influence.

The micromanipulation assembly (6) positioned at the sub-section of the liquid experimental assembly (2) is integrated with the magnets (5). The micromanipulation assembly (6) changes the direction of the magnetic field by moving and the micro robot (3) coated with ferromagnetic coating layer (1) is directed to the desired position.